Photosensitive electroluminescent indicating apparatus

Claim 1

AN INDICATOR COMPRISING FIRST CIRCUIT MEANS PROVIDING ALTERNATING CURRENT, VARIABLE GAIN AMPLIFIER MEANS CONNECTED AND RESPONSIVE TO THE OUTPUT OF SAID FIRST CIRCUIT MEANS, MEANS CONNECTED TO SAID AMPLIFIER TO VARY THE GAIN THEREOF, A GASEOUS COLUMA CONNECTED AND RESPONSIVE TO THE OUTPUT OF THE SAID VARIABLE GAIN AMPLIFIER WHEREBY A PORTION OF THE SAID GASEOUS COLUMN IS ILLUMINATED AND THE PORTION ILLUMINATED IS PROPORTIONAL IN LENGTH TO THE OUTPUT OF SAID VARIABLE GAIN AMPLIFIER, SAID GASEOUS COLUMN BEING CONFINED IN A TRANNSPARENT HOUSING, A SERIES OF PHOTOCONDUCTIVE CELLS ARRANGED ALONG SAID GASEOUS COLUMN AND IN VISIBLE RANGE OF SAID GASEOUS COLUMN SUCH THAT AS THE ILLUMINATED PORTION OF THE GASEOUS COLUMN INCREASES IN LENGTH MORE OF THE SAID PHOTOCONDUCTIVE CELLS ARE PLACED IN THE CONDUCTING STAE DUE TO THE ILLUMINATION OF THE GASEOUS COMUMN FALLING ON SAID PHOTOCONDUCTIVE CELLS, A SECOND SOURCE OF ELECTRICAL POWER, A SERIES OF ELECTROLUMINESCENT STRIPS EQUAL IN NUMBER TO THE NUMBER OF SAID PHOTOCONDUCTIVE CELLS ARRANGED IN A COLUMN AND EACH INDIVIDUALLY CONNECTED IN SERIES TO A RESPECTIVE PHOTOCONDUCTIVE CELL AND ALSO TO SAID SECOND SOURCE OF ELECTRICAL POWER SUCH THAT SUCCESSIVE ELECTROLUMINECENT STRIPS ARE ILLUMINATED AS THEIR RESPECTIVE PHOTOCONDUCTIVE CELLS ARE RENDERED CONDUCTING BY ILLUMINATION OF SAID GASEOUS COLUMN.